Crosslinked resin particles are widely used for paint, resin molding, adhesives, ink, cosmetics, printing plates, photoresist and like. The crosslinked resin particles are generally prepared by an emulsion polymerization method, a grinding method and a so-called post-emulsion method (Japanese Kokai Publication 156717/1985). The post-emulsion method is a method wherein a resin is dispersed in water and three dimensionally crosslinked within the dispersed resin particles to form crosslinked resin particles which are then take out from water.
In the post-emulsion method, however, since the surface of the obtained crosslinked resin particles is easily plastified, fusion bonds between particles often occur during the water removing step and large fused particles are obtained. Also, water to be removed is trapped in the large fused particles. These problems are seriously observed when the resin component to be dispersed in water is thermoplastic and has a low glass transition temperature (Tg), for example acryl rubber, polybutadiene, polyisoprene, chloroprene, poly-epsilon-caprolactone and polytetramethyleneglycol. The crosslinked resin particles prepared by the post-emulsion method from such thermoplastic resin also have poor redispersibility in an aqueous medium and have therefore not been practically produced.